What are the different irrigation methods and techniques for Frost protection

[tractorparts]

Last week I was reading articles about the dew point and when you should turn on your overhead irrigation. I was scanning and speed reading quite a few articles a lot of articles. I'm pretty sure I saw something about under tree irrigation with micro jet misters or just microjet sprinklers. At the time I was looking for other information so I didn't take the time to really analyze that technique. Now that my curiosity has me wanting to go back and read that particular method I'm having a hard time finding that particular article. So I am interested in hearing what others have tried and what they fine actually works best for them.
I have been inspired by the recent threads on this subject. I really probably should do something different my trees are getting too large to cover. Particularly Glen but a young Valencia Pride seems to be catching up to it quickly.

[Galatians522]

The orange groves around here use microjet sprinklers under the tree. However, tropicals need more water than that to protect them (unless you are using many microjets on each tree). If there is a light frost, microjets can warm things enough to protect the tree. If there is a hard freeze, only the parts under ice will survive (and only if you are forming enough ice to keep the temperature up). Windy conditions require more water. The more water you can put on over a broader area the better.

[tractorparts]

The orange groves around here use microjet sprinklers under the tree. However, tropicals need more water than that to protect them (unless you are using many microjets on each tree). If there is a light frost, microjets can warm things enough to protect the tree. If there is a hard freeze, only the parts under ice will survive (and only if you are forming enough ice to keep the temperature up). Windy conditions require more water. The more water you can put on over a broader area the better.

So there's overhead and under the tree. What is it called when the irrigation goes up into the scaffolding of the tree 3/4 the way up? Is that also called under the tree? Just want to make sure I have the proper terminology

[Galatians522]

Overhead typically refers to larger irrigation heads like wobblers, mini wobblers, or any other type of irrigation head that is designed to screwed straight into pvc (hard pipe) "risers" that come up above the tree. Under tree typically refers to smaller heads like microjets, spitters, drip, or bubblers that are designed to connect to poly pipe via a "spaghetti tube." However, there is every kind of variation imaginable. The key is not what kind of head you use, but how much water it puts out and where. Your picture is probably of a microjet system, by the way. They are typically designed to be installed on a short stake that is about a foot tall. Some heads will spray up another foot or two above that based on the angle of spray they were designed with.

[bovine421]

Overhead typically refers to larger irrigation heads like wobblers, mini wobblers, or any other type of irrigation head that is designed to screwed straight into pvc (hard pipe) "risers" that come up above the tree. Under tree typically refers to smaller heads like microjets, spitters, drip, or bubblers that are designed to connect to poly pipe via a "spaghetti tube." However, there is every kind of variation imaginable. The key is not what kind of head you use, but how much water it puts out and where. Your picture is probably of a microjet system, by the way. They are typically designed to be installed on a short stake that is about a foot tall. Some heads will spray up another foot or two above that based on the angle of spray they were designed with.

Excellent useful information going on in this thread thanks to Galatians
Some of the spaghetti tube micro Jets advertise 20 gallons per hour. So hypothetically if you used two overhead micro Jets. One on each side of the tree you would be Distributing 40 gallons per hour on Mango bloom. It seems as though the overhead while there's the potential of tree limb breakage. Life is not without risk would protect the bloom more than the other two methods. Going up through the scaffolding work well on open spreading trees but with varieties that have a dense canopy the irrigation didn't reach the outside bloom. With these spaghetti micro jets would filtration and pressure reduction be required?
Has not been an issue for the mini wobblers.

Hungry



Not so hungry!

You can visually see the slight changes in elevation determined who got frost and freeze and who did not. In our area the folks who live on high Sand ridges didn't receive much Frost or freeze. Others not so lucky

[bovine421]

Tractor parts! This is what I'm talking about here are two examples. This sweet tart has a mini wobbler up through the scaffolding.

Although it hasn't bloomed yet I feel as though the mini wobbler thoroughly coated the leaves with ice and sufficient water was running off the icicles. I feel as though it would have probably covered the bloom sufficiently to. The second photo is of a PPK


Because this tree was not thinned its canopy is dense.After the first Frost event I did not feel as though the outer canopy leaves were receiving sufficient water. So for the freeze then following night Frosty event I added a overhead mini wobbler on the east side of the tree where the vast majority of early bloom was located. The west side has less than a dozen bloom but is starting to push now. On this side of the tree there's nothing else that needs to receive Frost protection so I may use a micro jet with a 90-degree deflector that put out between 15 and 20 gallons per hour.

Westside bloom lightly toasted wobbler did protect leaves on this side.

The east side of the tree is a beautiful thing. The overhead wobbler banked money

[Galatians522]

We use mini wobblers over the top (similar to Bovine's picture) as well as two red microjets (color designates water volume) at the tree base. Skip all the technical stuff about dew point, wet and dry bulb temperature and just turn it on at 36 degrees. You won't be using a 500hp diesel pump that eats $ by the minute, so an extra hour or two is better spent getting a good nights sleep. Do what you can and leave the rest in God's hands.

[Jagmanjoe]

We use mini wobblers over the top (similar to Bovine's picture) as well as two red microjets (color designates water volume) at the tree base. Skip all the technical stuff about dew point, wet and dry bulb temperature and just turn it on at 36 degrees. You won't be using a 500hp diesel pump that eats $ by the minute, so an extra hour or two is better spent getting a good nights sleep. Do what you can and leave the rest in God's hands.

What about turning it on earlier for frost protection?  Here in our ugly microclimate pocket in Lakeland this morning we dropped below 40 around 3:30 this morning and, while our thermometer didn't drop to 36 until about 6:30, we have light frost.  I am thinking either my digital thermometer is off by a couple of degrees or we are seeing frost forming once it is under 40.  Does a light frost have an impact on mango trees when it happens above 36?

[tractorparts]

Bovine why don't you take one of those hoofers over citrus way and get some orange marmalade to put on those T-Bones

[bovine421]

We use mini wobblers over the top (similar to Bovine's picture) as well as two red microjets (color designates water volume) at the tree base. Skip all the technical stuff about dew point, wet and dry bulb temperature and just turn it on at 36 degrees. You won't be using a 500hp diesel pump that eats $ by the minute, so an extra hour or two is better spent getting a good nights sleep. Do what you can and leave the rest in God's hands.

What about turning it on earlier for frost protection?  Here in our ugly microclimate pocket in Lakeland this morning we dropped below 40 around 3:30 this morning and, while our thermometer didn't drop to 36 until about 6:30, we have light frost.  I am thinking either my digital thermometer is off by a couple of degrees or we are seeing frost forming once it is under 40.  Does a light frost have an impact on mango trees when it above 36?

I agree! I think turning on the spicket at 37 would be the prudent thing to do. Early with the water and the more of it the better. I really like these little red micro jets that I got today. Now that I can see the areas that mini wobblers didn't cover adequately. I can supplement with these red micro spinners.
Steak! I can barely finance a hamburger without a payday loan
Lol







Worked much better when I broke off the deflector

[Galatians522]

Move your thermometer to the coldest spot you can find (typically somewhere out in the open north of any cover or heat source). 37 is a good temperature to kick the water on. Better safe than sorry.

[Galatians522]

Quick update, I am re-thinking my comment about turning the water on at 36 degrees. This is probably good for citrus, but many of the plants we are growing are more cold sensitive and need all the help they can get. Some peope have started their water at 39 and that is probably what we will do from now on.

As far as a cost benefit analysis. I am told that it costs between $0.15 and $0.20 per horsepower for each hour to run an electric pump. So, if you have a 3hp pump it costs $0.60 per hour to run. If you run it an extra 3 hours it will only cost $1.80. That is less than the retail price of 1 top tier mango. Well worth it.

[roblack]

Lost 4 of the most mature soursop fruits after we hit 40F. Medium and smaller fruit do not appear to be effected, Going to irrigate soursop over night next time it gets close to 45F, if holding larger fruit.

[Jagmanjoe]

Well, last night's lows were supposed to be colder than tonight and it was 43 last night.  Tonight I get up at 2 in the morning and here we are again.  not freezing but not that far away so I just went out and turned my helter skelter wobbler system on to be safe as Channel 28 also suggested some patchy light frost is possible.  Soooo much easier than having trees covered and worrying about wind.

[bovine421]

Well, last night's lows were supposed to be colder than tonight and it was 43 last night.  Tonight I get up at 2 in the morning and here we are again.  not freezing but not that far away so I just went out and turned my helter skelter wobbler system on to be safe as Channel 28 also suggested some patchy light frost is possible.  Soooo much easier than having trees covered and worrying about wind.

Restful sleep is a good thing. Especially when you can hear Chica Chica Chica Chica in the background
Gallon for gallon you can't beat the mini (wobblers performance. I am experimenting with other micro spinners. I have found a use for the RKR in frost protection. Where the mini wobbler has an upward casting Arc of spray the rkr have a downward casting especially when their deflector tab is left in place. I have a PVC in the scaffolding 3/4 the way up with a mini wobbler which I screwed out and replaced with the RKR. I placed it 6in above the top canopy. I like the way it's umbrella downward casting pattern that covers the top of the canopy. My intentions are to use it for frost protection but if we get a forecast for Anna historic freeze to screw it out and replace it with the mini wobbler for scaffolding canopy extreme protection. I prefer the wobblers in between trees overhead because of their upward casting large diameter radius area of coverage. In some situations where you have an isolated tree some of these other spaghetti tubed micro spinners work nicely. Because this is all fresh in my mind and I can see the physical damage where irrigation did not reach I am fine tuning my system to be more efficient and effective just added another wobbler to the system. Making sure each Zone has proper PSI and Flow













5 gallons in 4:45 in the last micro sprinkler in that zone